Surgical wounds have been drained for many years by a variety of devices which are generally classified at the present time as "open" or "closed". Drainage systems are intended to evacuate blood, serum, pus, bile or other biological fluids which can accumulate in the depths of a wound or cavity and lead to various complications. Most widely employed are the "closed" systems which are designed to provide a conduit from the cavity through a tightly fitting perforation of the skin and subcutaneous tissues to an outside reservoir which draws fluids out with negative pressure. The system is closed to outside bacterial contamination in order to minimize the risk of inadvertent infection. Construction has generally been of semi-rigid or elastic tubular material, with perforations to allow body fluid to enter the tube. If it is necessary to drain more than one area simultaneously, then multiple drains have been required.
Surgical drains have also been classified as "active" and "passive". Active drains depend upon negative pressure to aspirate wound contents. Passive drains depend upon capillary action along the drain surfaces aided by fluctuation in intra-abdominal or intrathoracic pressures induced by respiration or body motion.
Surgical wound drains usually exhibit one or more deficiencies in conventional use. Some surgical drain devices permit ingress of bacteria into a wound cavity, and most drain devices become occluded by blood clots or accretions of coagulated protein mass or tissue debris, which results in premature termination of effective drainage function.
Many surgical drain devices have internal ridges or step-offs which provide the nidus for a build-up of clots along the hydraulic outflow pathway of wound or body cavity fluids, with resultant early obstruction of the drainage flow and failure to accomplish the primary function of complete fluid removal.
From a more fundamental viewpoint, the known surgical drain devices have not been designed with recognition of wound drainage as a multiphasic process and therefore the devices lack the versatility to satisfy the requirements of the multiphasic wound drainage process.
The earliest phase of wound evolution is an outpouring of liquid blood, serum, bile, intestinal digestive juices, and the like, including air. Shortly thereafter blood clots and inspissated fluids develop, followed by purulent material containing white blood cells, tissue debris, and bacteria.
Accordingly, it is an object of this invention to provide a polyfunctional surgical drain device for closed suction drainage systems.
It is another object of this invention to provide a surgical drain device which is adapted to accomplish long term wound drainage without premature clogging and wound fluid outflow stoppage.
It is a further object of this invention to provide a surgical drain device which is designed to satisfy the requirements of surgical wound drainage as a multiphasic process, capable of evacuating blood fluid before it clots, and clotted blood, body fluids, and tissue debris.
Other objects and advantages of the present invention shall become apparent from the accompanying description and drawings.
U.S. patents of general interest with respect to the present invention include U.S. Pat. Nos. 2,407,929; 3,406,691; 3,430,631: 3,815,608; 4,398,910; 4,445,897; and 4,465,482.